Printing telegraph apparatus



Feb. 16, 1954 R. D. SALMON ET AL PRINTING TELEGRAPH APPARATUS 2 Sheets-Sheet 1 Filed Aug. 29, 1952 Inventor R. D. SALMON-L. S. MUNCK- F. 0. L. TURNER ii- 4 Feb. 16, 1954 D SALMON ETAL 2,669,602

PRINTING TELEGRAPH APPARATUS 2 Sheets-Sheet 2 Filed Afi 29; 1952 i I Inventor R. D- SALMON L. S. MUNCK- 4 F. J. L. T URN ER Ailorne? Patented Feb. 16, 1954 PRINTING TELEGRAPH APPARATUS Reginald Dennis Salmon,

and Frederick James L England, assignors to Cr ited, Croydon,

Leslie Stampe Munck,

eslie Turner, Croydon, eed and Company Lim- England, a British company Application August 29, 1952, Serial No. 306,984

Claims priority, application Great Britain September 27, 1951 5 Claims. 1

This invention relates to printing telegraph apparatus and in particular to a page printing telegraph receiver incorporating an answer back mechanism which is released in response to the receipt of a distinctive who are you signal combination to transmit the characteristic code number of the apparatus or of the station at which the apparatus is situated.

In the specification of British Patent No. 644,850 there is described apparatus for automatically positioning the paper in a page printing telegraph receiver so that printing of a received message will commence at a predetermined position on the paper, usually at the top of a new form. This apparatus is brought into operation on the receipt of a form feed signal combination. In the arrangements described in this prior specification, in order to be effective at the receiver, this form feed signal combination is immediately preceded by a secondary shift signal combination which makes available a number of facilities not provided in the normal lower and upper cases associated respectively with letters and figures.

Where both form feed and answer-back facilities are provided, it is clearly desirable that the form feed opertion be completed and the paper fed into its final position before the answer-back transmitter is released.

Accordin to the present invention there is provided page printing telegraph apparatus comprising means operative in response to one or more distinctive signals of the first kind to move the paper into a predetermined position, means normally operative in response to a distinctive 5} signal of a second kind to release an answerback transmitter and means operative when said second distinctive signal is received after said first distinctive signal and before the paper has been moved into its predetermined position to delay the release of said answer-back transmitter until the paper has been moved into said position.

An embodiment of the invention as applied to a printing telegraph receiver is shown divided between Figs. 1 and 2 of the accompanying drawings. It is to be understood that the only parts of the receiver which have been shown are those material to the present invention. Other parts such as the supporting framework have been omitted in the interests of clarity. That part of the mechanism which is shown in Fig. 1 is mainly concerned with providing the form-feed facility while that shown in Fig. 2 is mainly concerned with the release of the answer-back transmitter.

2 Certain items interconnecting the two parts of the mechanism have been duplicated so as to appear in both figures.

It will be assumed that in the embodiment to be described, the invention is applied to a pageprinting telegraph receiver of the type disclosed in British patent specification No. 620,682. In this type of telegraph receiver, thesuccessively received code element of a signal combination are caused to set five storage members (assuming a five-unit code to be in operation) under the joint control of the receiving magnet and a selector cam sleeve released for rotation by the response of the magnet to the start element of the received signal combination. The selector cam sleeve during its rotation releases a translator cam sleeve for rotation and a cam on this translator cam sleeve causes the settings of the five storage members to be transferred to a first set of five permutation members in the form of notched discs cooperating with radially disposed bell crank levers and a second set of five permutation members in the form of tiltable vanes co-operating with notched function levers. The first set of permutation members acts in well known manner to select a character to be printed while the second set acts to select a desired function to be performed. I

In the accompanying drawings only one tiltable vane is shown (partly broken away) at I mounted on a spindle 2 and co-operating with three notched function levers, namely the Form Feed lever 3 (Fig. 1) the Answer Back lever 4 (Fig. 2) and the Figure Shift lever 5 (Fig. 2). The remainder of the signal selector and translator mechanism has been omitted since it forms no part of the present invention.

The operation of the mechanism shown in Fig. 1 on receipt of a form feed signal combination will first be described.

Reception of a form feed signal combination following the secondary shift signal combination causes the tiltable vanes such as I to take up a combinational setting which permits a spring 6 to rotate the form feed function lever 3 anticlockwise through a small are about its pivot I. This movement of lever 3 causes a leftward movement of a horizontal lever 8 pivotally attached at 9 to the form feed lever. Lever 8 is guided by a projecting pin It sliding in a slot in one arm of a bell crank lever H at present held stationary. This movement of lever 3 brings its left hand extremity into the path of a bail l2 fixed to a reciprocable shaft l3 (shown fragmentarily).

As soon as the form feed function lever B has is straying a :cam 41.

been selected as above described under the control of a cam (not shown) on the translator cam sleeve (shown diagrammatically at 14), another cam 15 on the same cam sleeve acts on a detent l6 to rotate the latter clockwise together with its spindle I! thus extending spring I3. This allows another spring i9 to draw a pawl into the teeth of a ratchet wheel 2 i fixed to a continuously rotating shaft 22. The pawl 20 spasm-11 attached to the function cam sleeve 23 which is thereby caused to rotate with shaft 22'. The arrangements just described constitute in fact a conventional type of friction clutch su'cli'a's is commonly to be found in printing telegraph apparatus. The function cam sleeve 23 is provided with a cam-shaped recess 24 in whichrests one end of a lever 25 freely mounted on a shaft 26. Fixed to lever 25 is a second lever 21 also freely mounted on shaft 25 and connected by a link 28 to a lever 29 fixed to shaft I3 carrying bail i2 The earn recess 24 asst; shaped-that fer aeh revolution of ears have 23; lever E-'5is i-m re gated once and imparts a like reiprcatory movement to "shaft I3 via members 27, 28 and 29. r :Ijhe first movement of bail i2 is in a clockwise direction and as it rotates it presses down the left hand'e'nd of lever '8 causii ig me latter to pivct about the point earnest the ''piill Ora spring 35. a um; same cheers l0 projecting from lever B s a ema es lever I"! to rotate clockwise abdutits pivot 3l;ag'aiiist"the can of a spring 32. The upper arm of bell crank'lever H is over extended to form a horizontal latching lever 33 normally engaging step 34 firmed me three armed lever 35 pivoted 35. n arm of lever 35 is provided with an exte sion 31 supporting one end of a lever 38 pivotally attaendat 35 to a 'leverfttl at'fore'sent stationary. As seen as three armed lever as is unlatched by Zifin 33, a time 4! rotates lever 38 in a clockwise direction about pivot 39 until it comes into con- 'tatwithawertieal can 42 integral with hor'icontal bail lZ an shaft [3. At the instant this occurs shaft I3 is nearing th'e'end of its clock- "wise intim ted the point architect between lever ss ana bail 42 is just to the right or protio'n 43 formed ham lever 38. As lever 38 rotates clockwise it depresses extension 31 of threearmed lever-35 causing'the latter to rotate clockabout pivot 36 so that the step 35 is brought 'above the level of latching lever 33. Also liked to shaft I3 is a segmental rack 44 nie'shing with a pinion 41s fixed to a short start v The first half-revolution of cam sleeve 23 eause'seam 4'! to rotate through 180 in an anticlockwise direction at the end of which a pin 43 projecting from the face of the strikes an aim-4e rermearrem a bell crank lever 50. This causes lever 5cm rotate by a small amount about its pivot 5l'th'us extending a sp'r'i'figsz and bringing a hacked and 53 clear r alarm 54 ektended'from a four-armed lever 55 pivoted at 55; Another-arm -5lof lever 59 carriesfa roller 53 as soon as arm 54 is freed from hooked end 53, a spring 59 rotates lever 55 anticlockwise about pivot 56 to bring roller 58 into contact with the periphery of cam '41.

Y All the-events so far described take place before or during the first half-revolution of cam sleeve 23 and the clockwise rotation of shaft I3.

As the cam sleeve begins its second half-revolut-ion, cam 4'! begins to rotate back ina'clo'ckwise direction-from its 180 position. As it 'does so,

spring '59 causes roller 58 to follow cam 41, the

printing to c'tiinmnce.

contour of which is such as to cause lever 55 to be rotated anti-clockwise about pivot 56. A rod projecting from an arm 5! of lever acts on a bell crank lever 62 to rotate it clockwise about its pivot 63 and an extension 64 of lever 62 rotates another lever 55 about its pivot 66 against the pull of a spring 61. Integral with lever is a seeker 58 which is thereby brought into ednta'ctwith the paper 59 wrapped around the platen 10.

As explained in said British Patent No. 644,850 the paper 69 is proi'rided with a hole H so located that it will be opposite the point of the seeker 68 when the paper is in the correct position for The platen 10 is provided with a circumferential groove 12 in the same plane as the hole ll. In describing the present embodiment it will first be assumed that the seeker 68 does in fact find a hole in the paper 69 denoting that the paper is in the right position. This hole would not then of course be in the'position indicated at H but would be"im= possible to show in its correct position in Fig. 1.

Half way through the second half revolution of cam 41, i. e. when cam sleeve 23 has turned through 270, roller 58 comes onto the lowest point of the periphery of cam 4'. and the'tip' of seeker 58 passes right through the hole'in the paper into the groove '12. Attached to arm 51 carrying roller 55 is a short shaft 13 on which is pivoted a lever M having a horizontal extension 75. At this'momenti. e. when lever '55 is in its extreme anticlockwise position-" a spring 18 f0- ta'tes lever 14 to bring extension-l5 undera step T! formed in the edge of a plate '18 pivoted at 19.

Continued rotation of cam 41 (froin2'70 to 360) causes four-armed lever 55' to be rotated clockwise about pivot 56 to bring seeker 68 out ofthe' hole in the paper H. At the same time extension'l5 engaging step i? in plate 18 causes the latter to rotate clockt'lise about its pivot "I9 against the pull of a spring 89.- An extension SI of plate 18 engages under a back edge '82 of tli'ree armecl lever 35 so that the latter'is rotated clockwise about its pivot 35. Ektension 31 or lever 35 rotates lever 38 anticlockwise about its pivot 39 thus extending spring 4| and bringing projection 43 out of the path of vertical bail 42.

During the return (anti-clockwise) stroke of vertical'bail #32 its companion horizontal bail 12 allows spring '35 to rotate lever 8 about pivot 9 in a clockwise direction. Pin It causes lever 11 to rotate in the opposite direction about pivot =8! so bringing the end-of latching lever 33 above, but clear of, step 34 on lever 35.

As "cam sleeve 23 completes its revolution and shaft l3 completes its return movement, hooked end 53 of bell crank lever 55 engages once more the horizontal arm '54 formed from lever 55.

By the time that the -function cam sleeve 23 approaches the end of its revolution the translator cam sleeve i4 has been arrested by means not shown but well known in the art. Thus cam l5 has returned to its initial position and detent I5 is again in the path of pawl '29 attached to function cam sleeve 23. As the latter coi'nplete's its revolution, detent l6 withdraws pawl 20 from the teeth of ratchet wheel 2i fixed to the continuously rotating shaft 22. lihus the "function cam sleeve is arrested at the end of one revolution. It is to be noted that the function cam sleeve 23 is similarly allowed to make justone revolution for each signal combination received (notonly the form feed signal'combination) with the exception of the answer back signal combination which may in certain circumstances cause it to make a plurality of revolutions as will be explained later.

It will now be assumed that when the seeker 68 is first presented to the paper 69 on the platen 10, the paper is not in its correct initial position and the seeker finds no hole therein. The immediate result of this is that the seeker is unable to rotate fully about its pivot 66 an similarly four-armed plate 55 is unable to rotate sufficiently to allow horizontal extension to engage under step 11 in plate 18. Thus when lever 55 is again rotated clockwise during the last part of the first revolution of cam sleeve 23, plate 18 does not move from the position shown. This in turn means that three-armed lever 35 is left in its extreme anti-clockwise position and projection 43 on lever 38 is left in the path of the vertical bail 42. anti-clockwise direction to its initial position it comes into contact with projection 43 which is, however, so shaped as to allow the bail to slide over it when moving in this direction.

During the return (anti-clockwise) stroke of vertical bail 42 its companion horizontal bail i2 acts, as previously described, to allow spring to rotate lever 8 clockwise about pivot 9. Since, however, three-armed plate is still in its extreme anti-clockwise position, levers 8 and I I can only rotate until the end of latching lever 33 comes into contact with lever 35 below the step 34. No further action takes place until the function cam sleeve 23 approaches the end of its revolution.

It has already been explained that each received signal combination (except sometimes the answer back) causes the function cam sleeve 23 to make one revolution and then to be arrested. Although in the revolution which follows the receipt of the form feed signal combination it is established whether the paper is in the right position or not, at least one further revolution of this cam sleeve is required to perform a form feeding operation should such prove to be necessary. These further revolutions of the function cam sleeve 23 may conveniently be brought about by the reception of repeated form feed signal combinations. Thus the operator at the transmitter either depresses the form feed key lever a plurality of times or else depresses the form feed key lever simultaneously with the run out key lever, thus causing the form feed signal combination to be sent automatically a plurality of times. In either event the result at the receiver will be the same, namely that the detent It will be held out of the path of the pawl 20 each time the latter completes arevolution.

Assuming then that the seeker 68 finds no hole in the paper on platen 19 and that the function cam sleeve 23 continues to rotate, the vertical ball 42 is again rotated clockwise and comes into contact with projection 43 on lever 38, which lever is still in its extreme anti-clockwise position, As ball 42 continues to rotate it remains in contact with projection 33 and pulls lever 38 to the right. This in turn rotates lever clockwise about its pivot 83 against the pull of a spring 84, normally acting to keep the upper end of the lever against a stop 85. Pivotally attached at 86 to lever 40 is a form feed pawl 81 provided with a cam surface 88 is held in contact with a fixed pin 89 by spring 4!. As lever 38 is moved to the right by vertical bail 42, pawl 81 As the latter returns in an s.

is similarly moved to 1 the right and the shape of cam surface 88 is such that spring 4| is permitted to rotate pawl 81 anti-clockwise by a small amount about its pivot 36 so bringing pawl tooth 90 into engagement with one of the teeth on a ratchet wheel 9| fixed to the platen spindle 92 carrying the platen 19.

Continued clockwise rotation of vertical bail 42 during the first half of the second revolution of the function cam sleeve 23 causes feed pawl 81 to rotate ratchet wheel 9| in an anticlockwise direction by an amount sufficient to advance the paper 69 on platen 10 by the space of one line of printing.

During the second half of the second revolution of cam sleeve 23 the seeker 68 is operated as previously described to ascertain whether or not the paper 69 is now in the correct position.

If the paper is in the correct position then lever 38 is lifted clear of vertical bail 42 as previously described and continued reciprocation of the ball has no further eifect on the feed pawl 81.

If the paper is not in the correct position, the

' platen continues to be rotated, one step at a time for each revolution of cam sleeve 23. As soon as the seeker enters the hole 1| in the paper, form feeding is suspended in the mamier previously described.

In order that the form feed mechanism shall be ready to function the next time a form feed signal combination is received, the mechanism must be reset into the condition shown in Fig. 1. In particular, it is necessary to disengage extension 15 of lever 14 from step 11 in plate 18. This is achieved on the receipt of the first line feed signal combination.

Receipt of the line feed signal combination causes the selection by the tiltable vanes (such as I) of the line feed function lever (not shown). At the same time the form feed function lever 3 is pushed out into its unselected position if it has not already been pushed out on receipt of a previous signal combination. When the line feed function lever is selected it acts through mechanism (not shown) to allow a lever 93 pivoted at 94 to fall onto a bail 95 fixed to shaft i3. There is a revolution of cam sleeve 23 associated with the receipt of the line feed signal combination and so bail 95 is first rotated clockwise and then anticlockwise in the same way as bails l2 and 42. As bail 95 rotates clockwise it engages a projection 96 on the lever 93 and thereby moves lever 93 in the same way as lever 81 was moved by bail 42. The line feed pawl 91 is linked with lever 93 in the same manner as the form feed pawl 81 is linked with lever 38. The continued clockwise rotation of bail 95 causes the line feed pawl tooth 98 first to engage one of the teeth in a ratchet wheel 99 fixed to platen spindle 92 and thereafter to rotate the platen 19 by an amount sufficient to feed the paper 69 thereon by the space of one line of printing. Just before the completion of the clockwise rotation of bail 95 a pin I09 projecting from lever 93 strikes lever 14 and rotates it anticlockwise by a small amount about pivot 13. This brings extension 15 of lever 14 clear of step 7'. in plate 18 and the latter is brought back to its initial position by spring 80. This in turn allows three-armed lever 35 to rotate anticlockwise about pivot 36 until step 34 comes once again into contact with latching lever 33. During its return stroke (anti-clockwise) bail 95 merely rides over projection 96 on lever 93.

rotated clockwise about its pivot falso fixed to :shaft Although the seeker "cam 41 isireoiprooated 'for'every receivedsignal combination, the-seeker $8 is only required to operate when'a form: feed condition has been set up. To'this end; a rod illI projects from the uppermost arm I02 of threearmedlever 35. Only if lever 35 is in its anticlockwise position which only occurs when a form feed signal'co'mbination has beenreceived is "four-armed lever 55 free to be rotated anticlockwise by spring 59 and so to present the seeker to the paper on the platen.

The operation of the answer back mechanism will'now be described'with particular reference to Fig. 2.

The answer back mechanism is prepared for operation by the'receipt of the Figure Shift. sig- 'nal combination and -released for operation (in normal --circumstances) by the subsequent receipt of'the who'are youfsignal combination.

The receipt :of the :figure shiftsignal combinationbauses the vanes :such as I to assume :a 'cornbinational setting which permits the figure shift function lever 5 to be selected by being I03 under the pull of a spring I54. The figureshift function 1ever'5 carries two projecting pins I05.and I06 on which is slidably mounted a detent member I01 lying parallel to the function lever and as the latter moves into selected position, the member I'OI is similarly rotated clockwise about a pointhea'rits lower extremity. This brings an extension MB of member IIlI into the path of 'a bail I'IIEI'fixed'to-sha'ft I3. The receipt of the figure shift signalcombination causes shaft I3 to be reciprocated :as previously described and 'as itrotates.initiallyclockwise, bail 09 acts on extension I08 to press member Iii! downwards against the pull ofa spring 'II!!. This movement of member .01 :acts through-a rocking lever II Igpivoted at II2, torotate clockwisea lever 'II3 fixed to a shafthIM journalled .in'the frame of the machine.

Also fixed to shaft I I4 is another lever I'I5 which is normally held downby a spring IIB onto a lower step II'I formed in a member II B forming part of the stationary framework. "As lever II3 rotates clockwise it liftsthe end of lever II5 clear of step II'Izand allows a spring H9 to draw lever II'5/and shaft 'II4 bodily in the direction of the arrow until the-end of lever I I5 comes onto an upper 'step I20 formed in member I I3. The effect :of this: longitudinal movement of the shaft H4 and lever H5 is twofold, namely:

(:a.) .It positions the turned ever end I2.I of

lever H5 just above the end of the answer-back pawl lever I I2, and

-(b) It positions the free end of a lever 'I23 II4-just above the turned over end I24 of the answer back release lever I25.

When the who-are-you signal combination is received the vanes such as I take up a combinational setting which permits the answer-back function lever 4 to be selected by being rotated clockwise about its pivot I26 under the pull of a spring I27. At the same'time, the figure shift function -lever5 is rotated anti-clockwise into its unselected position if it has not already been rejected by the receipt of an intervening signal combination. The answer back function lever A carries two projecting pins I28 and I29. On pin I26 is slidably mounted the lower end of a .detent member I36 while :a spring. I3I urges the upper end of member I30 to follow ,pin- I29. As function .lever 4 moves clockwise into selected position, member I30 is similarly rotated clock- 8 wise about a point near itsslower extremity. :This brings an extension I32 ofmember I30 intotthe path of a bail :I 33xfixed to .shaft I3. .(Thelast mentioned items appear in both figures'of the drawing.)

The .receiptof thewho-are-you signal combination causes shaft I3 to be reciprocated as previously described and as itrotates initially clockwise, bail I33 acts on extension I32 to press member I30 downwards against the pull .of *8. spring I34 (Fig. .2). Member I30 acts on .a turned-over end portion I35 of the-answer back release lever I25 to rotate thelatteranti-clockwise about its'pivot I36 so causing turned-over end 124 to :rotate lever I23 '(previously'positioned above end I24 the manner already described) clockwise together with its shaft H4. Thisinturn causeslever II5 to rotate clockwise so that its turned-over end I2I "rotates pawl lever I22 clockwise about its pivot I3'I against the pull of a spring I38. A'pawl. I39 pivoted on lever I22 and-connected therewith by'a spring 1:40-engages a' tooth of a ratchet wheel I4L1lxed to a shaft I42'car-rying the answer back drum (notxshown) and as pawl "lever I22 rotates clockwise, pawl I39 advancesratchet wheel III :by the space 'of :one tooth (in a clockwise direction).

The answer-back drum is of 'well :known-con- 'struction, being provided with a plurality of wards or teeth out to correspond to'the characteristic code combinations of "the station 'to'be identified. These co-operate with thermal .set of permutation members in the transmitter mechanism of the teleprinter. Also co-operating with ratchet wheel 'I'4I is a feedipawl I 43 (shown input) which is reciprocated once in every revolution of the transmitter cam sleeve (not shown). 'Pawl'l43 is arranged to advance the drum one tooth at a time thereby causingthe -answer-back code combinations to be sent out "sleeve produces no effect on the ratchet wheel f'When pawl I39 advances ratchet wheel MI by the space of one tooth in response 'to the receipt of the who-are-you'signal combination the feed pawl I43 is permitted to engage the tooth..im mediately behind the cutaway portion I44. At the. same time, the transmitter camJsleeveis set in rotation (by means not shown) and thus pawl I43 is reciprocatedto advance the ratchet wheel and the answer back drum one step .ata time until all the combinations on the drum have been transmitted. Thereafter the pawl I43 comes againv into the cutaway portionI44 and the transmitter cam sleeve .is arrested.

With the mechanism so far described it is .necessary .for the operator to ensure that he has sentasuflicientnumber of .form feed signalcom- 'binations to position the paper at the receiver correctly before he depresses his who-are-you key lever.

According to the present invention, however, it is only necessary for the operator to send the secondary shift, form feed, figure shift and whoare-you combinations as a group of four signals whereupon steps are automatically taken at the receiver to ensure that the paper is in its correct position before the answer-back drum is released.

In carrying out embodiment of the invention additional mechanism is involved which will be introduced as it becomes necessary in the ensuing description.

' It has already been explained that upon re" ceipt of the form feed signal combination (following the secondary shift combination) the form feed function lever 3 (Fig. 1) moves into selected position and initiates a cycle of events during which the seeker 66 is presented to the paper 66 on the platen "Iii to ascertain whether or not the paper is in the required position for the commencement of a message. If the seeker finds no hole, showing that the paper is not in its correct position, the mechanism is left in a condition Where every subsequently received signal combination will cause a successive line feed operation to take place until the correct position of the paper is reached. In this condition of the mechanism of Fig. 1, lever II is in its extreme clockwise position and until the seeker finds a hole and form feeding is suspended. (Jo-operating with lever II is a lever M5 pivoted at I 46 and having two turned over extensions Id'I and l i-8. A spring anchored to a pin I 56 projecting from lever II urges extension I67 of lever I65 into contact with lever II and so causes lever I46 to move in sympathy with lever II. Thus when lever i I is rotated clockwise into its operated position at the beginning of the form-feed cycle, lever I is similarly rotated clockwise about its pivot I46. This brings the right hand end of extension I 48 into the position shown dotted in Fig. 1. Normally this end of extension I66 is in front of a cutaway portion I 5 I in the upper end of the answer back detent member I 36 so that the latter is free to follow the answer back function lever 4 as it moves into selected position. In its dotted position, however, the end of extension I 43 of lever I46 acts as a blocking member to prevent the detent member from following the answerback function lever although it does not prevent the latter from moving into its selected position.

It will now be assumed that the form feed signal combination is immediately followed by the lettershift and who-are-you combinations and that several further revolutions of the function cam sleeve 23 are necessary before the form feeding operation may be said to be completed.

When the figure shift combination is received, the form feed function lever 3 is rejected but it is to be noted that the form-feed condition having been once established persists until the paper 69 has been fed to its correct position. Thus not only is lever 38 left in a position to co-operate with pawl 42 to perform successive line feeds but blocking member I 38 is left in the path of the answer back release lever I36.

When the figure shift combination is received the function cam sleeve is released for one revolution and this causes the paper on the platen to be fed forward one line. The receipt of the figure shift combination also causes the answerwill remain there :3

10 back trip mechanism to be prepared in the manner already described.

When the "who-are-you signal combination is received the form feed condition is still set up and the resulting revolution of the function cam sleeve causes the paper on the platen to be fed forward another line. The seeker establishes that the form feed condition must be maintained for the present and consequently extension I48 of lever I 45 is in a position to prevent detent member I36 from following the answer-back function lever i as the latter moves into its selected position. Until detent member I30 is allowed to follow function lever t and the answerback drum cannot be released.

Since it is assumed that the platen 16 must be further rotated in order to bring the paper 69 into correct position before the answer-back drum is released, it will be apparent that arrangements must be provided to prevent the function cam sleeve 23 from being arrested after it has completed the two revolutions associated respectively with the figure shift and who-are-you combinations. Pivotally mounted at I52 on the answer-back function lever 4 (Fig. 2) is a short lever I53. A spring I54 anchored to pin I55 on lever It tends to keep a turned over end I56 on top of a step I51 formed in a lever I58 pivoted at I56. A further spring I66 also anchored to pin I65 resiliently connects levers t and I58.

As the answer-back function lever 4 moves into selected position, lever I63 pushes lever I58 so that the latter rotates clockwise about pivot I59 and away from its stop I6I. This movement of lever I58 brings its lower extremity off an upper extension I62 of a bell crank lever I63 pivoted at I64. A spring I65 anchored in the machine is thus permitted to rotate lever I63 clockwise about pivot I63 until a lower extension I65 formed from the horizontal arm of lever I63 comes into contact with the underside of the answer-back release lever I25. At the same time a horizontal extension I66 of the vertical arm of bell crank lever I63 is brought into close proximity with a vertical member I61. This member I61 is arranged to slide vertically in two guides, only one of which has been shown at I68, and is formed with a slot in which slides a pin I69 projecting from a lever I10 fixed to shaft I'I.

Referring to Fig. 1 it will be remembered that upon receipt of any signal combination the translator cam sleeve I6 is released for one revolution and a cam I5 thereon rotates detent I6 clockwise together with its shaft I! and thereby allows the ratchet clutch of the function cam sleeve to be engaged for one revolution. Subsequently in normal operation the detent is returned to its former position so that it can disengage the function cam sleeve at the end of its revolution.

In the present circumstances, when detent I6 is rotated clockwise it acts through shaft I! and lever I70 (Fig. 2) to slide member I6! into a lower position. A projection III on member I6'I isso shaped as to cam extension I66 of lever I63 out of its downward path but once member I67 has reached its lower position spring I65 brings extension I66 onto the upper edge of projection I II. When spring I8 (Fig. 1) attempts to replace the detent I6 in the path of the pawl 20 driving the function cam sleeve 23, member I6! tries to rise but the shape of projection I'II prevents it from passing extension I66 in this direction. Thus detent I6 is held out of the path of pawl 20 and the function cam sleeve 23 continues to rotate until the paper on platen I0 has been fed 11" to its correct position,.thepositiorrof the paper being tested once during each revolution by. the seeker 68.

When the seeker finds a hole in the paper form feeding operation is suspended as previously described, and the lever II (Fig. 1) is replaced in its original position. Thisbrings extension I48 back in front of cutaway portion II in detent member I30 thus allowing the latter tube pulled by spring I3I into line with the answer-back lever 4 (Fig. 2) which is still in its selected position. The next downward stroke of bail I33 depresses the detent member I30 thus operating the answer-back release lever I25 and causing the answer-back drum. to be released as previously described.

As detent member. I30 descends a horizontal extension I12 thereof rotates lever I53 anticlcckwise so that end I56 comesoif step I51 in lever I58. This permits spring I60 to rotate lever I58 in an anti-clockwise direction by an amount which is limited by. thelower end of.the lever coming up against the side of upper exten sion I62 on lever I63. As detent member I30. continues to descend it acts on the lower extension I65 of lever I63: to rotate the latterv anticlockwise about its pivot I64. This brings the extension I66 of the'vertical arm of lever I63 away from projection I'1-I- on member I61 and thus permits spring I8 (Fig. 1) to replace de-- tent I6 in the path 'of pawl 20 so as to arrest the function'camsleeve 23 at the end ofits present revolution. At the same time, the horizontal arm of lever- I63 (-Fig. 2) is moved downwards until the upper extension I63 thereof. is once again below the lower end of lever I56. Thisenablesspring I60 tov rotate lever I58 anticlockwise until its upper and comes into contact with stop I6I. In this position, the lower end of lever I58 is again vertically above:the upper extension 62 of lever I63-and so as detent mem-' ber I30 follows theretreating. bail I33 upwards,

lever I63 is prevented from againrotatingclockwise under the pull of spring. I65.

When the next signal combination-is received the answer back function lever 4 is rotated anticlockwise into its rejected position so extending spring I60 and allowing spring I64 to replace the end I56 of lever I53 on step With the mechanism so far describ ed,-a serious condition is liable to occur if the answer back function tion lever 4 by means of a spring I16 anchored to a pin I11 projecting from lever 4. As func tion lever 4 moves anticlockwise into its rejected position it rotates lever l13'anti-clockwise about its pivot I14 and the lower end of the lever I13 acts on a ramp I18 formed as an exten- I51 in lever I58.

v lever 4 is rejected for any reason. before the form feeding is completed and the sion. of the-horizontal arm of bell crank lever;

I63. This in turn causes lever I63 to rotate am ti-clockwise andpermits itto be locked up "once more in a position where it no longer prevents the arrest of the function cam sleeve 23.

While the principles of the invention have. been described above in connection with specific embodiments and particular modificationsthere-- of, it is to be clearly understood that this derscription is made by way of example and not as a limitation on the scope of the invention.

What we claim is:

1. Page printing telegraph apparatus. comprising means operative in response tov a tinotive signal of a first kind to movethe'paper; into a predetermined position, means normally operative in response to a distinctive signal ofa second kind to release an answer-back'trans mitter and means operative when said second. distinctive signal is received after said first diltinctive signal and before the paper has been. moved into said predetermined position to delay the release of saidanswer-back transmitter un-- til the paper has been moved into said position.

2. Page printing telegraph apparatus com prising a first function member selectable on receipt of a first distinctive signal to initiatethe. moving of the paper into a predetermined posiv' tion, a second function member selectableon receipt of a second distinctive-signal, arelease member controlled by said second function member, means normally urging said release member to follow said second function member into selected position means operative. when. said release member has followed said. second; function member into selected position. to. re.- lease and answer-back transmitter. and meansv controlled by said first function member. for. preventing said release member from followingsaid. second function member until the. paper. has. been moved into said predetermined position.

3. Page printing, telegraph apparatus as claimed in claim 2, further comprising a seeker member, means for moving. said seeker member into engagement with-the paper and means 'responsive to said "seeker member entering. a perforation in said paper to sup ress any rmmedi ately succeeding line feed operation.

'4. Page printing telegraph apparatus. as claimed in claim 2, further comprising abiocking'memb'er, means operable upon the. selection of said first function member to. position. said blocking member in the path of said release. member andmeans responsive to said seeker member entering a perforation in said paperto remove said blocking: member. from the path of said release member.

5. Page printing telegraph apparatus as claimed in claim 3, further comprising mehfil: responsive to the receipt of saidnrst signal or signals for moving said seeker memberinto engagement with said paper todetermine whether the paper is in said predetermined p0 sition prior toany movement of said paper- REGINALD DENNIS SALMON. LESLIE STAMPE MUNCK.v FREDERICK JAMES LESLIE No references. cited. 

